/Engine/Source/Developer/SourceControl/Public/SourceControlHelpers.h
CheckOutOrAddFile()
static bool CheckoutOrMarkForAdd ( const [FString](API\Runtime\Core\Containers\FString) & InDestFile, const [FText](API\Runtime\Core\Internationalization\FText) & InFileDescription, const [FOnPostCheckOut](API\Developer\SourceControl\FOnPostCheckOut) & OnPostCheckOut, [FText](API\Runtime\Core\Internationalization\FText) & OutFailReason )